합천지역 농촌지하수의 질산성질소 오염 기원 구명

유훈선 ( Hun Sun Yu ),강동환 ( Dong Hwan Kang ),권병혁 ( Byung Hyuk Kwon ),고동호 ( Dong Ho Go ),황종환 ( Jong Hwan Hwang ) 대한지질공학회 2010 대한지질공학회 학술발표회논문집 Vol.2010 No.-

산성광산배수의 수질관측 및 중금속 유출질량 산정

유훈선 ( Hun Sun Yu ),권병혁 ( Byung Hyuk Kwon ),김박사 ( Park Sa Kim ),김광호 ( Hwang Ho Kim ),강동환 ( Dong Hwan Kang ),김병우 ( Byung Woo Kim ) 한국물환경학회 ( 구 한국수질보전학회 ) 2010 공동 추계학술발표회 Vol.2010 No.-

합성수지 제조 사업장의 코팅공정에서 발생하는 유기화합물 저감에 관한 개선 사례

유훈종,Yu, Hun-Jong 대한산업보건협회 2008 산업보건 Vol.240 No.-

드론 관측을 통한 순천만 갯벌과 갈대밭 상부 대기의 이산화탄소 농도 분포 연구

강동환,조원기,윤연수,유훈선,장선웅,김동립,박정환,송영철,최용재,Kang, Dong-hwan,Jo, Won Gi,Yun, Yeon Su,Yu, Hun Sun,Jang, Seon Woong,Kim, Dong Lib,Park, Jeong Hwan,Song, Young Chul,Choi, Yong Jae 한국환경과학회 2020 한국환경과학회지 Vol.29 No.7

In this study, carbon dioxide concentration and air temperature at different elevations were observed and analyzed in the upper atmosphere of mud flat and reed beds at low tide in Suncheon Bay. The carbon dioxide concentration and air temperature sensors were mounted on the drone, and the carbon dioxide concentration and air temperature by altitude (5 m, 10 m, 20 m, 40 m) at five points in the tidal flat and reed beds were observed in the morning and afternoon. The carbon dioxide concentrations in the upper atmosphere of the tidal flat ranged from 453.0 to 460.2 ppm in the morning and 441.6 to 449.7 ppm in the afternoon. The carbon dioxide concentrations in the upper atmosphere of the reed beds ranged from 448.9 to 452.4 ppm in the morning and 446.0 to 454.4 ppm in the afternoon. The carbon dioxide concentrations in the upper atmosphere of the tidal flat was higher in the morning than in the afternoon, and the carbon dioxide concentration decreased as the altitude increased. The carbon dioxide concentration in the upper atmosphere of the reed beds was similar in the morning and afternoon at all altitudes, and the carbon dioxide concentration decreased as the altitude increased. The correlation coefficient between carbon dioxide concentration and air temperature observed in the tidal flat in the morning was -0.54 ~ -0.77, and the correlation coefficient between carbon dioxide concentration and air temperature observed in the afternoon was 0.56 ~ 0.80. The correlation coefficient between carbon dioxide concentration and temperature observed in the morning in the reed field was low, below 0.3, and the correlation coefficient between carbon dioxide concentration and air temperature observed in the afternoon was 0.35 ~ 0.77. In the upper atmosphere of the tidal flats and reed beds, the linear function was suitable for the change of carbon dioxide concentration as a air temperature, and the coefficient of determination of the estimated linear function was higher in the afternoon than in the morning. Through this study, it was confirmed that the carbon dioxide concentration in the upper atmosphere of the tidal flat and the reed beds was different, and the increase rate of carbon dioxide concentration in the upper atmosphere of the tidal flat and the reed beds was higher in the afternoon than in the morning.

낙동강 유역에 위치한 폐수처리시설 최종방류수의 수질과 항생물질 분석

박경덕,강동환,조원기,유훈선,윤연수,김병우,Park, Kyeong-deok,Kang, Dong-hwan,Jo, Won Gi,Yu, Hun Sun,Yoon, Yeon Su,Kim, Byung-Woo 한국환경과학회 2020 한국환경과학회지 Vol.29 No.8

In this study, the antibiotic components in the final effluent from the 12 wastewater treatment facilities located in the Nakdong River basin were investigated, and the correlation between organic matters, nutrients and antibiotics was analyzed. In the final effluent of the wastewater treatment facilities, three sulfonamides antibiotics (sulfamethazine, sulfathiazole, sulfachlorpyridazine) and tetracyclines antibiotics (oxytetracycline, doxycycline) were detected. Sulfamethazine were detected at all points and ranged from 10.398 to 278.784 ng/L. Sulfathiazole were detected at 6 points (Andong, Gumi, Hapcheon, Miryang, Uiryeong, Haman), and ranged from 23.773 to 144.468 ng/L. The correlation coefficients between sulfathiazole and TSS, COD, TOC, NH₃-N, NO₂-N, and T-N components were high in the range of 0.73 to 0.92. The correlation coefficient between sulfamethazine and T-N was 0.48, and the correlation with the rest of the water quality components was low. The correlation coefficient between sulfamethazine and sulfathiazole was 0.78. Through this study, it was confirmed that the concentration of sulfonamides antibiotics was higher than the concentration of tetracyclines antibiotics in the final effluent of 12 wastewater treatment facilities in the Nakdong River basin, and the concentration of sulfathiazole increased with organic matters and nutrients.

일광 폐광산 갱내에서 유래된 산성광산배수의 중금속 유출특성

강동환 ( Dong Hwan Kang ),권병혁 ( Byung Hyuk Kwon ),유훈선 ( Hun Sun Yu ),김선옥 ( Sun Ok Kim ) 대한지질공학회 2010 지질공학 Vol.20 No.1

본 연구지역에서 2009년 3월부터 9월 사이에 5개 지점(배경수(BW), 산성광산배수(AMD0, AMD1, AMD2, AMD3))에서 수온, pH, Eh, EC, DO 성분 등이 현장에서 6회 관측되었으며, 폐광산 갱내 출구부(AMD0) 지점에서는 유량이 측정되었다. 일광 폐광산에서 유출되는 산성광산배수는 pH 3 이하의 강산성수이며, Eh 성분은 400~600 mV의 범위이었다. 산성광산배수의 EC 값은 주변 배경수에 비해 10배 이상 높았으며, DO 성분은 유출지점 하류부로 갈수록 대기와의 접촉을 통해 그 값이 증가되었다. 산성광산배수 내 중금속 이온의 농도는 Fe>Cu > Zn>Mn >As >Cd 순이었으며, Fe 성분의 농도가 81.870~474.30 mg/L 로서 가장 높았다. 중금속 성분별 최대농도 관측시기는 5월(As, Cd), 6월(Fe), 7월(Cu, Zn, Mn) 이었으며, 최소농도는 4월(Cd, Mn)과 9월(Fe, Cu, Zn, As)에 관측되었다. 산성광산배수에 용존된 중금속의 유출질량은 Fe 성분 53.44 kg, Cu 성분 6.25 kg, Zn 성분 5.26 kg, Mn 성분 2.13 kg, As 성분 0.14 kg, Cd 성분 0.04 kg 정도이었다. 폐광산에서 갱내에서 1일 동안 유출되는 6개 중금속의 전체 질량은 67.26 kg 이었으며, Fe 성분이 전체 유출질량의 79% 정도를 차지하고 있었다. Field water qualities (temperature, pH, Eh, EC, DO) was monitored by 6 times March to September 2009 on background water (BW) and acid mine drainage (AMD0, AMD1, AMD2 and AMD3 points), and flow rate was measured on AMD0 point. Acid mine drainage flowed out from abandoned Ilgwang mine were high acid waters that lower than pH 3, and Eh component was ranged 400 to 600 mV. EC measured on acid mine drainage were higher over 10 times than background water, DO component was increased by reaction on the air during the water flow from AMD0 point to AMD4 point. Heavy metal concentrations in acid mine drainage were ordered Fe > Cu > Zn > Mn > As > Cd, and Fe concentration was highest for 81.870~474.30 mg/L. Monitoring periods measured maximum concentrations of heavy metals were May for As and Cd, June for Fe, July for Cu, Zn and Mn. The periods measured minimum concentrations were monitored April for Cd and Mn, September for Fe, Cu, Zn and As. Discharge mass of heavy metal components were calculated 53.44 kg for Fe, 6.25 kg for Cu, 5.26 kg for Zn, 2.13 kg for Mn, 0.14 kg for As and 0.04 kg for Cd, respectively. Total discharge mass of heavy metal components were calculated 67.26 kg for 1 day, and Fe component was taken 79% of total mass.

갯벌, 논 및 산림 부지에서 지표와 대기 사이의 이산화탄소 플럭스 계절/공간 변동 분석

강동환 ( Dong Hwan Kang ),권병혁 ( Byung Hyuk Kwon ),유훈선 ( Hun Sun Yu ),김박사 ( Park Sa Kim ),김광호 ( Kwang Ho Kim ) 한국환경과학회 2011 한국환경과학회지 Vol.20 No.8

For this research, they were monitored CO2 flux and environmental factors (CO2 concentration, soil temperature, soil moisture, soil organic carbon, soil pH, soil Eh) in foreshore, paddy field and woods sites at the winter season (January 2009) and the summer season (September 2009). Seasonal and spatial variations for monitored data were analyzed, and linear regression functions of CO2 flux as environmental factors were estimated. CO2 fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the winter season were shown -8 mgCO2m-2hr-1 and -25 mgCO2m-2hr-1, respectively. CO2 fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the summer season were shown 47 mgCO2m-2hr-1 and 117 mgCO2m-2hr-1, respectively. Thus, CO2 was sunk from atmosphere to surface at the winter season and it was emitted from surface to atmosphere at the summer season. CO2 fluxes in woods site were emitted 145 mgCO2m-2hr-1 at the winter season and 279 mgCO2m-2hr-1 at the summer season.

충돌 윈도우 크기 조정에 의한 탐욕적(Greedy) 노드문제 분석

한유훈(Yu-Hun Han),석승준(Seung-Joon Seok) 한국컴퓨터정보학회 2009 한국컴퓨터정보학회 학술발표논문집 Vol.16 No.2

IEEE 802.11 WLAN(Wireless LAN)은 효율성과 편리함으로 시장에 급격히 보급되었다. 이 IEEE 802.11 WLAN은 CSMA/CA를 기반으로 하는 DCF방식을 주로 사용하고 있으며, Contention Window, Backoff Size를 이용한 각 단말기들간의 자유 경쟁에 의한 전송 방식을 택하고 있다. 그 주된 방법으로 단말기는 CW를 설정하고 CW범위안에서 랜덤한 값을 정해 Backoff Counter를 줄여 채널을 점유하는 방식이다. DCF방식은 채널을 두고 여러 대의 단말기가 서로 경쟁을 함으로써 채널을 할당 받아 사용하게 된다. 본 논문에서는 이러한 채널 할당시 CW값을 조절하여 다른 단말기보다 채널을 빨리 할당받고 높은 처리량을 나타내는 탐욕적(Greedy) 노드문제에 대해서 분석하는 방법에 대해서 설명하려고 한다.

요추부 척추관 협착증의 후방 감압술에서 후방 인대의 보존 여부와 술 후 척추 불안정성과의 연관성: 포트홀(Port-Hole) 감압술과 후궁 아전절제술 간 비교 연구

정유훈(Yu-Hun Jung),나화엽(Hwa-Yeop Na),최세헌(Saehun Choe),김진(Jin Kim),이준하(Joon-Ha Lee) 대한정형외과학회 2020 대한정형외과학회지 Vol.55 No.1

목적: 요추부 척추관 협착증에서의 후방 감압술 시 극간인대 및 극상인대의 보존이 술 후 척추 불안정성의 예방에 미치는 영향에 대하여 밝히고자 했다. 대상 및 방법: 2014년 3월부터 2017년 3월까지 요추부 척추관 협착증에서 후방 감압술을 시행하고 1년 이상 추시관찰한 83명의 환자를 후향적으로 연구하였다. 대상자들을 수술의 종류에 따라 포트홀 감압술을 시행한 56명의 환자는 그룹 A로, 후궁 아전절제술을 시행한 27명의 환자는 그룹 B로 분류하였다. 임상적 결과를 평가하기 위해 Oswestry disability index (ODI), 요통과 방사통에 대한 시각통증점수(visual analogue scale, VAS), 신경성 간헐적 파행(neurogenic intermittent claudication, NIC) 전 보행거리가 수술 전후로 측정되었다. 영상의학적 결과를 평가하기 위해 수술 전 및 수술 후 매 6개월마다 직립상태에서 측면 및 굴곡-신전 단순 방사선 사진을 촬영해 전위 정도(slip percentage), 역동적 전위 정도(dynamic slip percentage), 각변위(angular displacement), 역동적 각변위(dynamic angular displacement)를 측정하였다. 결과: ODI (그룹 A에서 28.1에서 12.8로 호전; 그룹 B에서 27.3에서 12.3으로 호전), 요통에 대한 VAS (그룹 A에서 7.0에서 2.6로 호전; 그룹 B에서 7.7에서 3.2로 호전), 방사통에 대한 VAS (그룹 A에서 8.5에서 2.8로 호전; 그룹 B에서 8.7에서 2.9로 호전), 그리고 NIC 전 보행 거리(그룹 A에서 118.4 m에서 1,496.2 m로 증가; 그룹 B에서 127.6 m에서 1,481.6 m로 증가)는 두 그룹 모두에서 호전되었다. 다른 영상의학적 결과들에서 유의한 차이가 없었던 반면 역동적 각변위는 술 후 두 그룹간에 유의한 차이를 보였다(그룹 A에서 6.2°에서 6.7°로 증가; 그룹 B에서 6.5°에서 8.4°로 증가; p-value=0.019). 결론: 요추부 척추관 협착증에서의 후방 감압술시 극간인대 및 극상인대를 포함한 후방 인대의 제거는 술 후 역동적 각변위의 증가를 초래하며 후방 인대를 보존하는 포트홀(port-hole) 감압술을 통해 이를 예방할 수 있다. Purpose: To determine if sparing the interspinous and supraspinous ligaments during posterior decompression for lumbar spinal stenosis is significant in preventing postoperative spinal instability. Materials and Methods: A total of 83 patients who underwent posterior decompression for lumbar spinal stenosis between March 2014 and March 2017 with a minimum one-year follow-up period, were studied retrospectively. The subjects were divided into two groups according to the type of surgery. Fifty-six patients who underwent posterior decompression by the port-hole technique were grouped as A, while 27 patients who underwent posterior decompression by a subtotal laminectomy grouped as B. To evaluate the clinical results, the Oswestry disability index (ODI), visual analogue scale (VAS) for both back pain (VAS-B) and radiating pain (VAS-R), and the walking distance of neurogenic intermittent claudication (NIC) were checked pre- and postoperatively, while simple radiographs of the lateral and flexion-extension view in the standing position were taken preoperatively and then every six months after to measure anteroposterior slippage (slip percentage), the difference in anteroposterior slippage between flexion and extension (dynamic slip percentage), angular displacement, and the difference in angular displacement between flexion and extension (dynamic angular displacement) to evaluate the radiological results. Results: The ODI (from 28.1 to 12.8 in group A, from 27.3 to 12.3 in group B), VAS-B (from 7.0 to 2.6 in group A, from 7.7 to 3.2 in group B), VAS-R (from 8.5 to 2.8 in group A, from 8.7 to 2.9 in group B), and walking distance of NIC (from 118.4 m to 1,496.2 m in group A, from 127.6 m to 1,481.6 m in group B) were improved in both groups. On the other hand, while the other radiologic results showed no differences, the dynamic angular displacement between both groups showed a significant difference postoperatively (group A from 6.2º to 6.7º, group B from 6.5º to 8.4º, p-value=0.019). Conclusion: Removal of the posterior ligaments, including the interspinous and supraspinous ligaments, during posterior decompression of lumbar spinal stenosis can cause a postoperative increase in dynamic angular displacement, which can be prevented by the port-hole technique, which spares these posterior ligaments.

다운증후군 청소년의 중증 고관절 골관절염에서 고관절 유합술

정유훈(Yu-Hun Jung),신근영(Keun-Young Shin),이주영(Joo-Young Lee) 대한정형외과학회 2021 대한정형외과학회지 Vol.56 No.2

다운증후군은 가장 흔하게 발생하는 염색체 이상 질환으로 일생 동안 약 28%에서 고관절의 골관절염을 동반하게 된다. 다운증후군에서 수술적 치료를 시행하게 될 경우에 의학적 관점에 더불어 환자의 정신적, 경제적인 요건 및 사회적 환경까지 고려하는 포괄적 접근이 필요하다. 청소년기 다운증후군에서 발생한 중증 고관절 골관절염에 대해 고관절 유합술을 시행하여 좋은 결과를 보여 보고하는 바이다. Down syndrome is the most common chromosomal disorder and is accompanied by hip osteoarthritis in approximately 28% of patients. This paper reports a case of hip arthrodesis as a treatment for severe hip osteoarthritis in adolescent Down syndrome patients. When performing surgical treatment of patients with Down syndrome, it is necessary to take a comprehensive approach that considers not only the medical point of view, but also the psychological and economic requirements of the patient and their social environment.